Roller-mill feed regulator



Aug. 24, 1954 w. Lr-'FLER ROLLER-MILL FEED REGULATOR Filed Nov. 28, 1951/NvENrQR Willy Lffze Patented Aug. 24, 1954 ROLLER-MILL FEED REGULATORWilly Lffler, Uzwil, Switzerland, assigner to Gebrder Bhler, Uzwil,Switzerland Application November 28, 1951, Serial No. 258,667

Claims priority, application Switzerland December 9, 1950 4 Claims.

' 1 My present invention relates to improvements in means forregulatingthe rate'of feed through a pivoted segmental gate of a rollermill.

In known regulators of this kind, a regulating element connected to thegate through Ya linkage and biased through the outflowing grain, tendsto open the gate against the action Of a spring. Such known regulatorsgenerally are of such sensitivity as to give origin to a pumping actionwhereby the gate is pulsatingly opened and closed so as to affect veryunfavorably the power input of the mill units and of the entire mill.

Such known regulator elements, furthermore, generally are formed asinclined clacks or toggle levers which project far into the hopperspace, or are formed yas lrtree-like gable structures, which projectupwardly into the glass cylinder. These known regulator elements have agreat disadvantage in that the outflowing goods tend to accumulate belowthem whereby nests of moths may be formed which impair the regulation i.e. prevent the segmental gate from being entirely opened. In some ofthese known regulators, furthermore, the goods to be ground have to beretained in the hopper to a level high up in the glass cylinder in orderto allow the goods to be distributed over the entire length of thedelivery rollers.

Such disadvantages inherent to known regulators shall be eliminated bymeans of the feed regulator disclosed in my present invention in thatthe regulating element is formed by at least one piece of corrugatedsheet iron which hangs freely in the hopper and of which thecorrugations extend substantially parallel to the delivery rollers sothat the goods acting on to the corrugated faces cause the delivery gateto be opened and closed uniformly smoothly.

One form of my present invention is shown by way of example in theaccompanying drawing in which: p

Fig. 1 shows a vertical cross-section through the hopper of a rollermill in operation, the segmental delivery or feed gate (6) being open,and

Fig. 2 is a vertical longitudinal section on the line II-II of Fig. 1,illustrating the heap of goods retained in the hopper.

The hopper I is defined by the space above the delivery or feed rollers2 and between the two stationary walls 3 and 4, while 5 is the feedtrough.

Y The segmental feed gate 6 on one hand has an upwardly projecting arm 1fixed thereto, which carries an adjustable finger 8 to one end of whichis pivoted a roller 8. The gate 6 on the other hand is biased by aregulable tension spring 9 to the closed position. To a regulating shaftI0 are fixed an arm II which has a track forthe roller 8', and a bauleor cover sheet I2. The latter extends through the entire length of thehopper I, i. e. it is as long as the feed rollers 2.

To the baiiie I2 are xed two arms I3 in which is rotatably mounted a rodI6 to which are fixed two regulating elements I4. Each of the latterconsists of a piece of corrugated sheet iron of which the corrugationsrun either parallel to the feed rollers 2 or slightly slope downwardlytowards the ends thereof. The corrugation faces of each element I4 areinclined at an angle of approximately 30 with respect to the verticalplane through the rod I6. The latter is journaled in recesses of the twoarms I3 so as to be readily removable therefrom. The confining wall 4 isfxedly arranged, but is readily removable. Above the hopper I isdisposed a glass inflow cylinder I5 of known construction through whichthe goods run into the hopper I.

The mode of operation of the regulator described is as follows:

Since the baille` I2 here is shortened to such an extent thatpractically no goods can accumulate below the same and below the wall 4,the entire hopper space I is free of baffles and like means and theinflowing goods can unimpededly move downwardly to the segmental gate 6.The two regulating elements I4, which are interconnected through therod' I 6,. do not disturb the downward flow of the goods, but on thecontrary aid the uniform distribution of the goods over the entirelength of the rollers 2.

When the goods are heaped up in the hopper I, they act laterally on tothe corrugations of the elements I4, as shown by the little arrows inFig. 1, and tend to push the same downwardly against the action ofspring 9, with the result that the gate Ii is slowly and gently openedWhen the heap in hopper I decreases in height the reaction of the twoelements I4 is delayed so that the gate 6 is reclosed only slowly andgradually.

When the goods are delivered to the hopper I at an'irregular rate, theregulator 6--I4 does not react or only so little as topractically'exclude any pumping action or pulsating delivery. Whenemptying the hopper I, the goods still react on the lowermostcorrugations of the two elements I4 so as to hold the gate stillslightly open until the hopper I is entirely empty.

When there are no more goods in hopper I, the two regulating elements I4together with the two arms I3 are in their topmost position,l and thegate 6 is entirely shut. When, however, the

roller mill is fully loaded, the said elements and arms are in theirbottommost position without, however, touching the rotary feed roller 2.The heaping level of the goods in the hopper I may be adjusted, asdesired, by changing the tension ofthe spring 9 of gate 6. Normally inoperation, the goods still should be visible in the `lower portion ofthe glass cylinder I5 in order to allow the attendant to control thethroughput.

The spacing between the twol regulating elements I4 is somewhatsmaller'than the diameter of the glass cylinder I5 in the case of shortroller mills, and approximately equal to said diameter in the case oflong mills. The said spacing as well as the width of the elements I4 areessential for a good distribution of the goods over the entire length ofhopper l.

Dynamometer tests have disclosed that a roller mill equipped with thenovel feed regulator described, requires less power input than a rollermill equipped with a conventional regulator in which troublesome loadfluctuations arise on account of the pulsating or pumping action feed.

What I claim as new and desire to secure by Letters Patent, is:

1. In a roller mill feed regulator having a hopper with multiple walls,said hopper being open at its top for the receipt of the goods to beground, feed rollers at the bottom of said hopper and a spring regulatedgate adjacent to the feed rollers, said feed rollers and said gateclosing said bottom, a balile in the path of said goods while theydescend downwardly by gravity, and linkage between said baie and gateextending outside of said hopper to open or close the gate, thecombination of a supporting member on said baffle extending inwardly -ofsaid hopper, a gate regulating member pivotally connected with saidsupporting member and disposed in the approximate median of saidgoods insaid hopper and extending vertically downwardly towards and in proximityto said gate and to one of said feed rollers, said regulating memberbeing in the form of at least one plate of corrugated sheet iron, ofwhich the corrugations extend substantially parallel to said feedroller, whereby on the goods descending in the hopper space, free of anyini-- peding means and unimpededly to said gate, the goods act laterallyon said corrugations, which tend to push said plate downwardly to slowlyand gently open said spring controlled gate, and when goods diminish intheir flow with less push against said corrugations, said gate slowlyand vgradually closes, said opening and closing of said open at its topfor the receipt of the goods to be r ground, feed rollers at the bottomof said hopper and a spring regulated gate adjacent to the feed rollers,said feed rollers and said gate closing said bottom, a bale in the pathof said goods while they descend downwardly by gravity and linkagebetween said baffle and gate extending outside of said hopper to open orclose the gate, the combination of a supporting member on said baffleextending inwardly of said hopper, two regulating plates withcorrugations in said hopper, said regulating plates being spaced fromeach other and being pivotally connected with said supporting member,and disposed in the approximate median of said goods in said hopper andextending vertically downwardly towards and in proximity to said gateand to one of said feed rollers, and a series of downwardly inclinedfaces on said plates, substantially parallel to said feed rollers,whereby on the goods descending in the hopper space, free of anyimpeding means and unimpededly to said gate, the goods act laterally onsaid faces of said regulating plates, whereby said plates tend to movedownwardly to slowly and gently open said spring controlled gate, andwhen the goods diminish in their now with less push against said faces,said gate slowly and gradually closes, said opening and closing of saidgate taking place practically without any pumping action or pulsatingdelivery of the gate.

' 3. In a roller mill feed regulator having a hopper with multiplewalls, said hopper being open at its top for the receipt of the goods tobe ground, feed rollers at the bottom of said hopper and a springregulated gate adjacent to the feed rollers, said feed rollers and saidgate closing said bottom, a baille in the path of said goods while theydescend downwardly by gravity, and linkage between said baffle and gateextending outside of said hopper to open or close the gate, thecombination of a supporting member on-said baie extending inwardly ofsaid hopper, a gate regulating plate pivotally connected with saidsupporting member, and disposed in the approximate median of said goodsin said hopper and extending vertically downwardly towards and inproximity to said gate and to one of said feed rollers, and a series ofcorrugations on said regulating plate, said corrugations beinglongitudinally slightly inclined towards the two ends of the feedrollers, whereby on the goods descending in the hopper space, free ofany impeding means and uninmpededly to said gate, the goods actlaterally on said corrugations, thereby tending to push said platedownwardly to slowly and gently open said spring controlled gate, andwhen the goods diminish in their flow with less push against saidcorrugations, said gate slowly and gradually closes, said opening andclosing of said gate taking place practically without any pumping actionor pulsating delivery of the gate.

4. In a roller mill feed regulator having a hopper with multiple walls,said hopper being open at its top for the receipt of the goods to beground, feed rollers at the bottom of said hopper and a spring regulatedgate adjacent to the feed rollers, said feed rollers and said gateclosing said bottom, a bailie in the path of said goods while theydescend downwardly by gravity, and linkage between said baille and gateextending outside of said hopper to open or close the gate, thecombination of a supporting member on said baffle extending inwardly ofsaid hopper, a gate regulating plate pivotally connected with saidsupporting member, and disposed in the approximate median of said goodsin said hopper and extending vertically downwardly towards and inproximity to said gate and directly above one of said feed rollers, anda series of downwardly inclined faces on said plate, substantiallyparallel to said feed rollers, whereby on the goods descending in thehopper space, free of any impeding means and unimpededly to said gate,the goods act laterally on said faces, thereby tending to push saidplate downwardly to slowly and gently open said spring controlled gate,and when the goods diminish in their flow with less push against saidfaces, said gate slowly and gradually closes, said opening and closingof said gate taking place practically Without any pumping action orpulsating delivery of the gate.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 333,570 Strong Jan. 5, 1886 1,324,832 Lawson Dec. 16, 19191,775,369 Moog Sept. 9, 1930

